Soft handover control adopted in W-CDMA is an example of control in which one mobile station (terminal) is connected to a plurality of base stations. Patent Document 1 Japanese Patent Application Laid-Open No. 2005-86688, for example, discloses a scheme in which, in communication between a conventional mobile station and a plurality of base stations controlled by soft handover, when the relay switching apparatus (base station control apparatus) as a data branch/merge point on the communication path is changed, the termination point of the protocol for soft handover control is changed to eliminate redundant routing paths. This scheme avoids redundant routing paths even when the mobile station moves across base stations that are subordinate to different base station control apparatuses.
Also, Patent Document 2 National publication of translation No. 2005-510950, for example, discloses a scheme in which base stations introduce a hybrid-type ARQ (Automatic Repeat reQuest) protocol to reduce the loads on the resources of the radio interface between the base and mobile stations.
Also, there is a scheme which determines the processing for sending measurements about scheduled data from base stations to a controlling base station control apparatus that controls the base stations, and in which a serving base station control apparatus (which is, among the controlling control apparatuses, an apparatus capable of data transmission of lu connection (an interface between the core network and a system composed of one base station control apparatus and a plurality of base stations and mobile stations) with the core network as a switching network) obtains the provided bit rate of at least one base station connected to a mobile station, and it is sent from the serving base station control apparatus to the controlling base station control apparatus. This processing enables the controlling base station control apparatus in the mobile communications systems to perform congestion control of uplink transmissions having guaranteed bit rates, and also reduces the load on the interface between the base stations and base station control apparatuses. Such a scheme is disclosed in Patent Document 3 Japanese Patent Application Laid-Open No. 2006-191554, for example.
In a scheme as described in Patent Document 1, in which the termination point of the protocol is changed when handover is conducted by changing the relay switching apparatus corresponding to a base station control apparatus, the resources of radio communications are controlled by a high-order apparatus like the relay switching apparatus; accordingly, when a large number of base stations communicate simultaneously with one mobile station, the control of resources is extremely complicated and it is difficult to quickly provide the mobile station with local information from individual base stations. Also, it is not possible to merge different schemes, e.g. to allow coexistence of W-CDMA and Super 3G.
Now, in general, controlling radio communication resources by a high-order apparatus is extremely complicated for the reasons shown below:
Adjustment of time differences between individual paths (routes) is required;
All routes have to be always used for mobile stations;
Mobile stations and base stations always have to report information about measurements of all routes to the high-order apparatus;
The high-order apparatus has to perform ranking and sorting; and
When a plurality of mobile stations are in the same area, the consumption of resources, the management of measurement information, and the adjustment of time differences between routes are necessary for the number of terminals times the number of routes.
Also, in a scheme as described in Patent Document 2, in which part of the functions of the high-order apparatus is transferred to base stations in order to perform large-capacity radio communication from the base stations to mobile stations, it is not possible to send local information in individual areas around the mobile stations, and it is not possible to allow coexistence of different communication schemes, as in Patent Document 1.
Furthermore, in a method as described in Patent Document 3, in which a base station control apparatus learns provided bit rates of base stations to control congestion, it is not possible, as in Patent Documents 1 and 2, to quickly provide mobile stations with local information from individual base stations, to send local information in individual places, and to allow coexistence of different communication schemes.
For a system in which a mobile station is capable of communicating simultaneously with a plurality of base stations, an object of the present invention is to provide a mobile communications system that is capable of reducing the redundancy of resources of base stations and a base station host apparatus including a base station control apparatus and a core network.
Another object of the present invention is to provide a mobile communications system that allows quick transmission of local information about each base station to a mobile station, transmission of local information in each place, and coexistence of different communication schemes.
For a system in which a certain mobile station is capable of communicating simultaneously with a plurality of base stations, a further object of the present invention is to provide a mobile communications system in which the mobile station can control radio resources of the base stations.
These and other objects, features, aspects and advantages of the present invention will become more apparent from the following detailed description of the present invention when taken in conjunction with the accompanying drawings.
According to a first aspect of the mobile communications system of the present invention, a mobile communications system comprises: a mobile station; and a plurality of base stations, wherein said mobile station is capable of communicating simultaneously with said plurality of base stations, and resources of said plurality of base stations are managed under the control by said mobile station.
According to a second aspect of the mobile communications system of the present invention, a mobile communications system comprises: a mobile station; and a plurality of base stations, wherein said mobile station is capable of communicating simultaneously with said plurality of base stations, and wherein said mobile station comprises: a data retain/discard judging function of judging whether to discard transmitted data while transmitting data to a certain base station among said plurality of base stations; and a base station selecting function of recognizing communication attribute values for judging whether communication lines of said plurality of base stations are good or bad, and when judging that said transmitted data should be discarded, selecting as a destination of transmission of said transmitted data a favorably communicating base station that has been judged to be favorably communicating on the basis of said communication attribute values among said plurality of base stations except said certain base station.
According to a third aspect of the mobile communications system of the present invention, a mobile communications system comprises: a mobile station; and a plurality of base stations, wherein said mobile station is capable of communicating simultaneously with said plurality of base stations, and wherein said mobile station recognizes communication attribute values for judging whether communication lines of said plurality of base stations are good or bad, and said communication attribute values include information about a moving direction and a moving speed of said mobile station, and on the basis of the information about the moving direction and moving speed of said mobile station, said mobile station provides control such that, among said plurality of base stations, a non-communicating base station that exists in a direction to which said mobile station moves nearer preferentially goes into a communicating state, and such that a communicating base station that exists in a direction from which said mobile station moves away preferentially goes into a released state.
According to a fourth aspect of the mobile communications system of the present invention, a mobile communications system comprises: a mobile station; and a plurality of base stations, wherein said mobile station is capable of communicating simultaneously with said plurality of base stations, and wherein said plurality of base stations each recognize a communication attribute value for judging whether its own communication line is good or bad, and said communication attribute value includes information about a moving direction and a moving speed of said mobile station, and on the basis of the information about the moving direction and moving speed of said mobile station, each of said plurality of base stations preferentially goes into a communicating state when the base station is not communicating and exists in a direction to which said mobile station moves nearer, and preferentially goes into a released state when the base station is communicating and exists in a direction from which said mobile station moves away.
According to a fifth aspect of the mobile communications system of the present invention, a mobile communications system comprises: a mobile station; a plurality of base stations; and a high-order apparatus communicably connected to said plurality of base stations, wherein said mobile station is capable of communicating simultaneously with said plurality of base stations, and wherein said high-order apparatus recognizes communication attribute values for judging whether communication lines of said plurality of base stations are good or bad, and said communication attribute values include information about a moving direction and a moving speed of said mobile station, and on the basis of the information about the moving direction and moving speed of said mobile station, said high-order apparatus provides control such that, among said plurality of base stations, a non-communicating base station that exists in a direction to which said mobile station moves nearer preferentially goes into a communicating state, and such that a communicating base station that exists in a direction from which said mobile station moves away preferentially goes into a released state.
According to a first aspect of the mobile station of the present invention, a mobile station constitutes a mobile communications system together with a plurality of base stations, and said mobile station is capable of communicating simultaneously with said plurality of base stations, wherein said mobile station comprises: a resource determining function of, on the basis of resource-related information about at least one base station among said plurality of base stations, determining which resource of said at least one base station is to be used, and a resource specifying function of, on the basis of the contents of the determination made by said resource determining function, specifying a resource to said at least one base station.
According to a second aspect of the mobile station of the present invention, a mobile station constitutes a mobile communications system together with a plurality of base stations, wherein said mobile station comprises: a data dividing function of dividing transmission data into a plurality of divided data pieces corresponding to a plurality of resources; and a data transmitting function of assigning said plurality of resources to said plurality of base stations set without overlap, and transmitting said plurality of divided data pieces being assigned to said plurality of resources.
According to the base station of the present invention, a base station constitutes a mobile communications system together with a mobile station, and said base station is capable of communicating with said mobile station, wherein said base station comprises: a data storage for storing data for transmission/reception; and a resource-related information transmitting function of recognizing resource-related information on the basis of a condition of storage in said data storage, and transmitting the resource-related information to said mobile station.